Apparatus for aberration detection and measurement
US7345735B2 · kind B2 · utility
Inventor
Key dates
| Filing date | Sep 27, 2006 |
| Grant date | Mar 18, 2008 |
| Priority date | — |
| Expiry date | Sep 27, 2026 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F7/706
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Aberrations in an optical system can be detected and measured using a method comprised of a test target in the object plane of a projection system and imaging a photoresist film with the system. The test target comprises at least one open figure which comprises a multiple component array of phase zones, where the multiple zones are arranged within the open figure so that their response to lens aberration is interrelated and the zones respond uniquely to specific aberrations depending on their location within the figure. This is a unique and new method of detecting a variety of aberration types including coma, spherical, astigmatism, and three-point through the exposure of a photoresist material placed in the image plane of the system and the evaluation of these images.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.